add synchronize to rust

rust/rox/src/parser.rs

@@ -191,6 +191,17 @@ impl Parser {
             Err(ParserError::ExpressionExpected(prev.line))
         }
     }
+
+    fn synchronize(&mut self) {
+        let _ = self.advance();
+        while !self.is_at_end()
+            && self.previous().unwrap().token_type != Semicolon
+            && !&[Class, Fun, Var, For, If, While, Print, Return]
+                .contains(&self.current_token.token_type)
+        {
+            let _ = self.advance();
+        }
+    }
 }
 
 /// Try to parse the provided tokens into an AST.